Means for supplying reduced pressure steam to heat exchanging apparatus



y 1940- J. VAN DER PLOEG 2,207,545

MEANS FOR SUPPLYING REDUCED PRESSURE STEAM 'IO HEAT EXCHANGING APPARATUS Filed March 26, 1938 Patented July 9, 1940 UNITED MEANS FOR SUPPLYING REDUCED PRES- SURE STEAM TO HEAT EXCHANGING AP- PARATUS Jelle van der Ploeg, Apeldoorn, Netherlands Application March 26, 1938, Serial No. 198,320

In the Netherlands March 18, 1937 5 Claims. (01. 122-459) In the pasteurization of milk, the vaporization of liquids in vacuum pan operations and for other similar purposes the liquid to be treated is usually heated by reduced pressure steam. This steam is ordinarily saturated steam generated by a boiler and supplied to the heat exchanging apparatus through areducing valve. Now, it is well known in the art that owing to this reduction of pressure the steam is, dependent upon the boiler pressure, more or less superheated and this superheat may have an injurious effect on milk and. other heat-sensitive liquids.

This inconvenience can be met, in accordance with my present invention, by injecting into the reduced pressure steama small quantity of boiler water substantially under boiler pressure, said water being thus evaporated by the superheat of the steam. If the amount of boiler water injected into the reduced pressure steam is suitably regulated, the result will be dry saturated steam. Said water need not necessarily be Withdrawn directly from the boiler but may be condensate of the high pressure steam.

It will be understood that this result is attained by the use of a small portion of the water from which the heating steam is generated, so that in recycling the steam after condensation thereof no foreign water is introduced into the boiler. Moreover, said water is under sulficient pressure to be atomized.

The water used for saturating the heating steam need not necessarily be withdrawn from the same boiler by which said steam has been supplied, but may be derived from another boiler of the same boiler plane. In this respect two boilers of a boiler plant are to be regarded as equivalents the one of the other.

In order that the manner in which the invention may be carried into practice may be fully understood, several embodiments, selected as examples, will now be described with reference to the accompanying drawing. In the drawmg:

Fig. 1 shows diagrammatically a steam boiler plant embodying the present invention, and

Figs. 2 and 3 are fragmentary views illustrating alternative embodiments of the invention.

Referring particularly to Fig. .l, 2 is a boiler in which saturated steam is generated which flows through conduits 3, 5 to a heat exchanging apparatus 4. The pressure of the steam supplied by the boiler is reduced to atmosphericvalue by a reducing valve 6. Thus, the steam in pipe 5 beyond valve 6 has a pressure of about one atsteam supplied by pipe 5, so that dry saturated 10 steam of atmospheric pressure flows to the pasteurizer or other heat exchanging apparatus '4.

The proper amount of water injected into the chamber 9 can be controlled by means of the valve in, or in any other suitable manner.

In the modification shown in Fig. 2 the conduit 3 for supplying steam under boiler pressure is incompletely insulated so that a suitable portion of the steam flowing therethrough condenses therein. Conduit 3 includes a separating vessel 12 which is connected by conduit H to the spraying nozzle 8. .The condensate accumulated in vessel l2 reaches the nozzle 8 through a control valve l3.

In the embodiment illustrated in Fig. 3, branch ll comprises a small, water cooled condenser M in which steam condenses.

That part of pipe 5 which is adjacent to chamber l is enlarged and contains a central streamline body 15, whereas a plate l6 having a great number of evenly distributed perforations I1 is provided between said pipe and chamber 1. Thus the steam enters said chamberin a uniform flow, which furthers the mixing thereof with the water injected and atomized by the spraying nozzle 8.

What I claim is:

1. In combination, a steam boiler, a heat exchanging apparatus, a conduit connecting said boiler with said heat exchanging apparatus, pressure reducing means in said conduit, a spraying nozzle opening in said conduit between said pressure reducing means and said heat exchanging apparatus, and means for supplying water to said nozzle at substantially the same pressure and temperature as the water in said boiler.

2. In combination, a steam boiler, a heat exchanging apparatus, a conduit connecting said boiler with said heat exchanging apparatus, pressure reducing means in said conduit, a spraying nozzle opening in said conduit intermediate said pressure reducing means and. said heat exchanging apparatus, a second conduit connecting a point ofsaid first conduit before said pressure reducing means with the said spraying nozzle, and condensing means in said second conduit.

3. In combination, a steam boiler, a heat exchanging apparatus, steam pressure reducing means, an incompletely insulated conduit for supplying steam from said boiler to said pressure reducing means, a second conduit leading from said heat exchanging apparatus, a second conduit connecting said boiler to said nozzle for supplying boiler water thereto.

5. In combination, a steam boiler, a heat exchanging apparatus, a conduit, connecting said boiler with said heat exchanging apparatus, pressure reducing means in said conduit, a spraying nozzle opening in said conduit between said pressure reducing means and said heat exchanging apparatus, and means for supplying water to said nozzle at substantially the same pressure and temperature as the water in said boiler, and means provided in said conduit intermediate the pressure reducing means and the nozzle for equalizing the flow of steam in said conduit.

vJELLE VAN DER PLOEG. 

